Jewelry Boutique

ok so i beat all the gym leaders (8) and i have all the pokemon that are the potential weaknesses of the rival"s

i have:

KADABRA: level 42
moves: Psychic, Light Screen, Psycho Cut, Future Sight.
item: twisted spoon
*** his HP is only 87, how do i make it higher without paying a fortune??***

DEWGONG: level 37 ( i will make it so he is 42+ )
moves: Rest, Blizzard, Surf, Sheer Cold
item: NeverMeltIce

HAUNTER: level 38 (again will be 42+)
moves: Sucker Punch, Shadow Claw, Shadow Ball, Dream Eater
Item: none

DRAGONAIR: level 38 (again 42+)
moves: Hyper Beam, Blizzard, Draco Meteor, Dragon Pulse
item: amulet coin

OH-HO: level 45
moves: Fire Blast, Extrasensory, Sacred Fire, Fly
item: Sacred Ash

RAIKOU: level 49
moves: Thunder, Flash, Hyper Beam, Hidden Power
Item: none

****i will remove and replace the following: Extrasensory and Dream Eater****

thanks